[Comparison of anti-ischemic effect of bepridil and diltiazem evaluated by exercise test in patients with coronary disease. A multicenter study. Groupe d'Investigateurs].

Bepridil (Cordium) is a calcium channel blocker which has been demonstrated to be effective in the preventive treatment of angina. Few controlled trials have compared bepridil to diltiazem (Tildiem), the reference calcium channel blocker. The objective of this study was to evaluate the efficacy and safety of bepridil in stable coronary patients. 148 patients (139 M, 9 F, mean age: 58 +/- 8.6 years), with documented coronary artery disease and positive stress test after 5 days of placebo were included. After double-blind randomization, they received bepridil (300 mg/day ion 3 doses), or diltiazem (180 mg+/day in 3 doses) for 15 days. A stress test was then performed under the same conditions as on inclusion. The anti-ischaemic efficacy of the two drugs was comparable. Total work increased from 4,552.4 +/- 2,179.4 Kpm a 6,103.2 +/- 2,849.2 Kpm with bepridil (p < or = 0.0001) and from 4,524.8 +/- 2,160.5 Kpm a 5,848.3 +/- 2,800.3 Kpm (p < or = 0.0001) with diltiazem, with no intergroup difference. Duration of effort was significantly prolonged: from 10.5 +/- 3.0 min to 12.5 +/- 3.3 min with bepridil (p < or = 0.0001) and from 10.5 +/- 2.9 min to 12.1 +/- 3.4 min with diltiazem (p < or = 0.0001), with no intergroup difference. The time to onset of 1 min of ST depression increased significantly between the two stress tests, from 8.36 +/- 2.7 min to 10.82 +/- 3.4 min with bepridil (p < or = 0.001) and from 8.02 +/- 3.0 min to 10.53 +/- 3.6 min with diltiazem (p < or = 0.001), with no significant difference between the two groups. The clinical safety of the two products was comparable. On the electrocardiogram, the QT interval was significantly prolonged with bepridil, from 368.6 +/- 37.5 msec to 393.6 +/- 38.7 msec (p < or = 0.0001), reflecting cellular impregnation of the drug.